Volume 10, Issue 2, 1996

Student created spreadsheet models for
teaching and learning: an initial self-evaluation of an experimental assignment

Guy Judge

University of Portsmouth

Introduction

Spreadsheets are now widely recognised both as essential tools
to be introduced to student economists as part of their IT
training and as potential tools for creating computer based
learning material. What is not always realised is that double
benefits can be derived from setting student assignments in which
they are to create spreadsheet applications which can also be
used as learning material for other students. The students who
create the spreadsheet models can learn a considerable amount
about both IT and economics, developing their skills and their
understanding, while at the same time new resources are created
which can be made available to other students to assist their
learning. This short paper provides an initial self-evaluation
of an experiment along these lines which has been conducted this
year with second year undergraduates at Portsmouth.

Some background

Readers of CHEER with long memories will know that I advocated
the use of spreadsheets in economics teaching as long ago as 1987
(see Judge (1987)) and I have been using them in a
variety of
courses since 1986. A collection of spreadsheet applications
suitable for undergraduate economics students was provided in
Judge (1990a). My preference has always been to
develop
spreadsheet skills in an integrated way with applications in
economics, quantitative methods and introductory econometrics.

In Judge (1990b) I distinguished six levels of
openness
in
spreadsheet applications for use with students. They ranged from
closed pre-programmed applications which students would use
(essentially as black boxes) through to completely open
worksheets where students would design their own worksheets.
In between these extremes were cases where students
would create functioning worksheets by following fairly detailed
instructions given to them on paper, or by modifying existing
programs to add extra features.

I was assuming that lecturers possessing the relevant skills
would create closed applications for use in their teaching (for
example, together with Neil Cooper, I developed a suite of Lotus
1-2-3 applications called MacroSpread and MicroSpread for use
with beginning students of economics - although these have now
been rather overtaken by WinEcon). On the other hand I have
always encouraged students to create programs to assist
them in their own work once they have developed their own
spreadsheet skills, and over the years I have seen many good
examples of this in practice, particulary from students on
statistics, econometrics and forecasting units. However such
applications have always been for the individual student's own
use. Up until now I have never asked students specifically to
create and document applications which could be used by other
students.

This year's experiment

The idea for my experiment came as a result of conversations that
I had with the Director of the University's Television Centre,
Dr Jeremy Miles, who believes that student created videos,
computer programs and other material can provide valuable
resources for subsequent generations of students. For example
students already benefit from looking at the dissertations of
earlier cohorts of students when preparing their own.

The task I gave to the students was to develop a spreadsheet
version of an economic model of their choice which could be used
by a student of economics to explore the model's properties or
for policy analysis. The application could be from any area
of economics but an accompanying written report had to provide
references to articles or books which had provided inspiration
for the model. The report had to give a clear account of the
purpose and functioning of the spreadsheet model to assist a
potential user. It also had to include a technical appendix
describing the design and construction of the spreadsheet. 50%
of the marks were to be awarded for the model itself, covering
the
design and functioning of the spreadsheet, with the remaining 50%
being awarded for the report and the clarity of the documentation
provided.

As well as being very open-ended in terms of the economic content
of the spreadsheet I was also very permissive about the software
used to create the application. Students could use DOS or Windows
versions of Quattro Pro, Lotus 1-2-3 or Excel to develop their
applications. There were several reasons for this. Firstly,
although Quattro Pro is still the officially recognised
spreadsheet package in the Business School and the one which
students had been shown how to use in their first year, Excel is
also available on the network as part of Microsoft Office and
some students have preferred to work with this package. Secondly
we have direct second year intake students transferring from
other universities (mainly in France and Malaysia) and these
students have sometimes been taught different packages. Thirdly
an increasing number of students have their own computers which
have often come with a partiular software bundle and it seemd
unecessarily restrictive to confine them to one particular
package which they may or may not have on their computer. Of
course the down side to this is that the courseware which has
been developed is now mixed in terms of its base package (55% of
the students used Quattro Pro, 40% used Excel and 5% used Lotus
1-2-3) but because of the requirement to document program design
and construction it should be possible to translate any good ones
for use with a different package.

To provide students with some initial ideas, in lectures I showed
them a number of working examples of spreadsheet models from many
areas of economics, and in computer lab practicals they created
or extended a series of spreadsheet models following printed
instructions which became progressively less detailed as they
developed their skills and understanding. I also referred
students to published examples in CHEER and elsewhere (they were
able to view some CHEER papers on-line having been taught how to
use the World-Wide Web earlier in the year). Students were given
the chance to consult me in surgery sessions and about a third
of them took advantage of this, mainly to check that what they
had chosen to work on would be acceptable.

The results of the experiment

The first reassuring outcome was that all students managed to
complete their work more or less on time (a few students were a
couple of days late and suffered penalty deductions from their
marks but late submissions were, if anything, less of a problem
than on other course units). Possibly this was associated with
the fact that details of their task were given to students right
at the beginning of the semester and regular reminders of the
need for a work schedule were given throughout the course.

Secondly all the submissions were of an acceptable standard,
although the pattern of marks had the appearance of two
overlapping distributions with one group content to provide a
satisfactory application and report without really stretching
themselves, but with some other students producing quite
outstanding results having clearly been stimulated by the whole
exercise. This was also reflected in the topics chosen. The
weaker students played safe and worked on applications very
similar to those they had been shown in lectures and seminars,
mainly linear programming (Ziggy McDonald's recent CHEER
article
was the single most cited item!), macrodynamics (although this
did include some examples which were not out of the multiplier-
accelerator stable) and input-output analysis (both using real
tables and for fictitious economies).

The more adventurous students attempted to develop applications
from material encountered on other courses or, in some cases,
building on their experience in the workplace. The best piece
of work was designed to explain the balance of payments and how
economic policy can affect various parts of the accounts. It
included six historical scenarios relating to various Chancellors
since Roy Jenkins and allowed users, with the benefit of
hindsight, to attempt to improve on their performance by setting
key variables such as interest rates and taxes at different
levels. The underlying model had been calibrated rather than
estimated and was not revealed on screen (although details were
provided in the appendix). It was relatively simple, but dynamic
in form, and would help users to see that some effects would be
virtually instantaneous whilst others would take longer to work
through. I am hoping that the student who wrote the application
will write an article about it for the next issue of CHEER.

Another excellent contribution was "Soap", a model of a
multiproduct firm providing launderette self-service and drop-off
washing facilities, dry cleaning and in store gaming machines.
The model was apparently based on a real world firm in Southsea
where the student works part-time. With underlying cost and
demand functions the manager could configure his prices in such
a way as to maximise profits, by trial and error or by applying
simple economic principles. Other impressive contributions
included a Cournot duopoly model, a couple of game theory
applications, a CAPM model and a simulation model of the
French economy. Not all the linear programming models were
unimaginative. For example there was a good one which looked at
the optimal selection of venues for rock-bands on a concert tour
and one relating to the choice of a salary, pension, medical and
other benefits package for employees which has already become the
prototype for an extended spreadsheet application to be worked
on during the summer by the student in his father's business.

Conclusions

Judged in terms of its value for the current second year students
I believe that this year's experiment has been a clear success.
Students have told me that they very much enjoyed working on
their projects and that they learned a considerable amount both
about the software and their chosen economic application. The
activity seems to have been able to stretch the ablest and most
enthusiastic students without causing undue problems for those
who have difficulties working with computers. In future years
a little more guidance might be necessary for students on the
production of the accompanying reports as some students lacked
the skills to incorporate screen grabs or were unsure of how to
document their work. It would also have been nice to have
students to present the fruits of their work to their colleagues
but in a semesterized system there isn't really the time. What
I might do is to get some current second year students to come
into next year's lectures and lab sessions to run through their
applications.

Looked at in terms of the resources created for use with other
groups of students I had perhaps been a little optimistic. In
the event probably only half a dozen or so of the 87 spreadsheets
models produced are in a good enough state to be used with little
or no modification. Perhaps this is all I should have expected
and until the experiment is repeated I won't know whether this
is a good rate of return or not. My feeling is that I could
probably have ensured more usable programs if I had been more
prescriptive in what I asked students to do, giving a tighter
list of topics to work on and providing more detailed guidelines
on courseware "look and feel". However in constraining students
in this way they may have found the exercise less stimulating.
Conversely, it could be argued, they might have learned valuable
practical lessons about meeting specific goals within a finite
time horizon if I had been more definite in what I asked of them.
I could have perhaps have had them working together in teams,
which might also have provided a built-in quality control factor,
although at the same time it would have added an extra
complication to the assessment of their work. Since the primary
objective of the course and the assessment is to develop the
individual student's own spreadsheet skills and their
understanding of quantitative economic models more weight must
be given to what they get out of the exercise than what they can
leave behind in terms of useable resources.